Updated tests to use new button classes. (#63040)

packages/flutter_localizations/test/material/date_picker_test.dart

@@ -104,7 +104,7 @@ void main() {
       home: Material(
         child: Builder(
           builder: (BuildContext context) {
-            return FlatButton(
+            return TextButton(
               onPressed: () async {
                 await showDatePicker(
                   context: context,
@@ -147,7 +147,7 @@ void main() {
       home: Material(
         child: Builder(
           builder: (BuildContext context) {
-            return FlatButton(
+            return TextButton(
               onPressed: () async {
                 await showDatePicker(
                   context: context,
@@ -187,7 +187,7 @@ void main() {
       home: Material(
         child: Builder(
           builder: (BuildContext context) {
-            return FlatButton(
+            return TextButton(
               onPressed: () async {
                 await showDatePicker(
                   context: context,
@@ -242,7 +242,7 @@ void main() {
               return Localizations(
                 locale: locale,
                 delegates: GlobalMaterialLocalizations.delegates,
-                child: RaisedButton(
+                child: TextButton(
                   child: const Text('X'),
                   onPressed: () {
                     showDatePicker(

packages/flutter_localizations/test/material/time_picker_test.dart

@@ -23,7 +23,7 @@ class _TimePickerLauncher extends StatelessWidget {
         child: Center(
           child: Builder(
             builder: (BuildContext context) {
-              return RaisedButton(
+              return ElevatedButton(
                 child: const Text('X'),
                 onPressed: () async {
                   onChanged(await showTimePicker(
@@ -52,7 +52,7 @@ Future<Offset> startPicker(
 }
 
 Future<void> finishPicker(WidgetTester tester) async {
-  final MaterialLocalizations materialLocalizations = MaterialLocalizations.of(tester.element(find.byType(RaisedButton)));
+  final MaterialLocalizations materialLocalizations = MaterialLocalizations.of(tester.element(find.byType(ElevatedButton)));
   await tester.tap(find.text(materialLocalizations.okButtonLabel));
   await tester.pumpAndSettle(const Duration(seconds: 1));
 }
@@ -248,7 +248,7 @@ void main() {
               child: Navigator(
                 onGenerateRoute: (RouteSettings settings) {
                   return MaterialPageRoute<void>(builder: (BuildContext context) {
-                    return FlatButton(
+                    return TextButton(
                       onPressed: () {
                         showTimePicker(context: context, initialTime: const TimeOfDay(hour: 7, minute: 0));
                       },